Field
The present disclosure relates to a crystalline form of ethyl 4,5-dihydro-5,5-diphenyl-3-isoxazolecarboxylate (isoxadifen-ethyl), to its preparation processes and to its use in agrochemical preparations.
Description of Related Art
Ethyl 4,5-dihydro-5,5-diphenyl-3-isoxazolecarboxylate (isoxadifen-ethyl) is a potent safener for sulfonylurea herbicides. Isoxadifen-ethyl has molecular formula of C18H17NO3. Its chemical structure is:

It is typically used to reduce the phototoxicity of sulfonylurea herbicides when applied on crops, such as maize, wheat and cereals.
The commercially available isoxadifen-ethyl, which is usually manufactured by the process described in U.S. Pat. No. 5,516,750, which is incorporated herein by reference for all purposes, is present in an amorphous state, the melting point which is about 78° C.-81° C.